1. Field
The field of the invention relates to circuit board inspection systems and methods. More specifically, the invention relates to x-ray systems for inspecting structural aspects of solder connections on circuit boards and inspection techniques.
2. Description of the Related Technology
Improvements in IC packaging technology have facilitated the tremendous increase in the performance of computers, PDAs, cellular phones, audio and video devices, and other equipment that use integrated circuits. The requirements for faster and more powerful chips for such devices necessitates increasing the density of packages for mounting IC chips. With the current trend of high density mounting of electronic parts on a substrate, the pitch of the leads has become smaller and the quantity of solder used for connecting these parts has also decreased. Because of the high density of the parts and their small size, inspecting solder connections has become increasingly difficult. In addition, functionally testing a circuit board to determine if its solder connections are adequate or troubleshooting a faulty board can result in severe damage to components on the board due to faulty solder connections.
As an alternative, X-ray inspection systems and methods can be used to inspect circuit boards to identify faulty solder joints and facilitate circuit board repair. Typically, such X-ray inspection systems include a loading process that requires the sample (e.g., a circuit board) to be attached to a surface or a device which holds the sample in a position for inspection inside a housing of the inspection system. The sample loading and unloading process can be arduous and slow due to the time required to place the sample inside the inspection system, and the need to mount the sample on a surface or in a device for the inspection. Often doors used to access the interior of the inspection system are large and heavy, and the position in which the sample is to be mounted is not easily reachable. Improvements to X-ray systems that address the above-described problems and other problems in the art, and that facilitate more flexible and efficient inspection procedures, are needed.